I've got a polygon shape layer, and each polygon has 200 or more vertices. I need to divide every polygon by attributes (vertices). Each polygon can not have more than 80 vertexes. I only found plugins that divide polygon by area.
I'm not sure i understand exactly what you are trying to do, but first things first, you will need this formula :
num_points( $geometry ) or
num_points( $geometry )-1 if you ignore the last closing point. It gives you the number of vertices (points) that is been used to create each polygon.
Then is when i'm not sure i understand what you need to do.
I would give the Polygon Splitter plugin a try, as it looks like you're using QGIS. It will allow you to split polygons into equal parts vertically, horizontally, or a combo of the two. It won't split by number of vertices, but if you play around with the splitting a little you should be able to ensure that all the polygons fall below your 80 vertex threshold.
An example of Polygon Splitter from another question: polygon split with predefined area